AUTHOR: WADE ROUSH | PUBLISHER: THE MIT PRESS | RELEASE DATE: OUT NOW
Given the size of our galaxy and the Universe beyond, there should be hundreds or even thousands of advanced civilisations out there trying to communicate with us. After World War II, the new science of radio astronomy inspired Cornell University physicists Giuseppe Cocconi and Philip Morrison to write a paper on ‘Searching for Interstellar Communications’. They believed that radio technology would be capable of detecting and joining in with the galactic community. Since then, except for a few false alarms, no sign of extraterrestrials has been discovered.
As Wade Roush observes, the famous Drake Equation was formulated to take into account all the factors that determine how many alien communicators might be out there. This considers the number of stars and planets that might support life, the fraction of planets where life might emerge, those that might evolve into intelligent organisms and develop technology, and the length of time an intelligent civilisation might exist. The result very much depends on our current expectations, on the one hand we can be more optimistic due to the discovery of exoplanets and organisms that can live in extreme habitats, yet our thinking about life-expectancy of civilisations might be coloured by the current Covid-19 pandemic (whereas in the past nuclear annihilation was a bigger influence on this equation).
Even the most pessimistic calculations indicate that our Milky Way galaxy should be rife with civilisations, giving rise to the Fermi Paradox that begs the question ‘why are we seemingly alone’? One brutal answer is that we are so rare there is no one else, or that the aliens are ignoring us, or we do not have the right technology to detect their signals.
Wade entertainingly provides chapters that look at the history of ideas and beliefs about the existence of aliens, how SETI (Search for Extraterrestrial Intelligence) became a scientific endeavour, where primitive alien life forms might exist in our Solar System or on exoplanets, and the various reasons why there is the ‘great silence’.
We found ourselves agreeing with his conclusion that, ‘There isn’t a single example of a UFO or an alleged alien visitation or abduction for which an unbiased scientist would resort to an extraterrestrial explanation sooner than a terrestrial or psychological one.’ That is fair enough, but Wade then goes on to note that SETI research has persisted very much in the style pioneered in the 1960s and that we should try to sidestep our anthropocentric assumptions about how aliens might think and cast our net wider. It would be ironic that flying saucers and the madness surrounding them really are ET visitors that blindside our scientists because they do not conform to their expectations.
Whatever your viewpoint, this is an excellent guide and introduction to SETI with plenty of insightful anecdotes, glossary, notes, further reading list, and index.
